1. Field of the Invention
This invention relates to a percutaneous absorption preparation. More particularly, it relates to a percutaneous absorption preparation which comprises a calcium salt of an acidic anti-inflammatory or analgesic drug having a carboxyl group as the active ingredient.
2. Description of the Prior Art
Acidic anti-inflammatory drugs such as indomethacin, mefenamic acid, flufenamic acid or ketoprofen have been widely used orally. However, the benefit of the full therapeutic effect thereof is often limited because of gastrointestinal side effects. Accordingly, the introduction of their rectal suppositories have allowed increased utilization for therapeutic purposes, it has however, been shown that the manifestations of peptic ulceration and rectal bleeding also occur with these suppositories. A rectal suppository of calcium salts of the acidic anti-inflammatory drugs is proposed and disclosed in Japanese Unexamined Patent Publication No. 162,560/1983, which however states that the concentration in the blood upon application of the rectal suppository is nearly equal to that of the rectal suppository of the corresponding free acid type drug.
On the other hand, gel preparations for external use of the acidic anti-inflammatory drugs or sodium salts thereof are known (e.g., U.S. Pat. No. 4,545,992 and U.S. Pat. No. 4,543,251).